1. Field of the Invention
The present invention relates to a digital contents distribution system for vending digital contents on an open wide-area network such as the Internet, and particularly to a digital contents distribution system that can implement the copyright management and charge management of the vended digital contents, and prevent the piracy thereof.
2. Description of Related Art
FIG. 16 is a block diagram showing a conventional digital contents distribution system disclosed in Japanese patent application laid-open No. 8-6784/1996, for example. In FIG. 16, the reference numeral 101 designates a user terminal; 102 designates use control means; 103 designates locking/destroying processing means; 104 designates software/copyrightable works; 105 designates continued use request processing means; 106 designates unlocking/reusing processing means; 107 designates management equipment of a distributor (vendor); 108 designates user information management means; 109 designates capability examination processing means; and 110 designates license renewal processing means.
Next, the operation of the conventional digital contents distribution system will be described.
The software/copyrightable works 104 embedding the locking/destroying processing means 103 are transmitted together with a key to the user terminal 101 of a vendee through a communication channel. The user terminal 101 exploits the software by unlocking it using the key. The software or work is automatically locked or destroyed on the expiration date in order to stop its operation. If the user sends a request for the continued use to the management equipment 107 through the continued use request processing means 105, the capability examination processing means 109 makes a decision referring to the contents of the user information management means 108, and the license renewal processing means 110 transmits, unless there is any problem, a new key or product to the user terminal 101 via a communication channel. The user terminal 101 receives the key or the product, and continues using the software or product until the next expiration date by unlocking it with the unlocking/reusing processing means 106.
With the foregoing configuration, the conventional digital contents distribution system has a problem of strictly restricting not only the expiration date, but also a range of available functions and data that can be referred to, and hence of being unable to generate a trial-use version of the contents by flexibly designating them.
Furthermore, since the conventional digital contents distribution system takes little care of an author, it has a problem in that it cannot provide a structure or processing flow that readily enables the author to manage the copyright, and a distributor to manage the charge.
In addition, since the distributor manages the encryption key of the digital contents in the conventional digital contents distribution system, the author must commit his or her product entirely to the custody of the distributor.
Moreover, the conventional digital contents distribution system has a problem of paying little attention to the embedding of user information into the digital contents, or the embedding is committed to the intention of the user.
Finally, the conventional digital contents distribution system has a problem in that since the charge timing is concurrent with the provision of the digital contents or decryption key, the user is apt to refuse it.